The countdown to London is less than 100 days, but Team USA athletes seem never to rest. TeamUSA.org tracks down where the top U.S. athletes are competing each week in the Olympic Weekend Preview. This week’s edition includes the Olympic Trials for wrestling, canoe/kayak, table tennis and more.

In two jam-packed days of men’s and women’s wrestling at the University of Iowa’s Carver-Hawkeye Arena, 18 spots on the U.S. Olympic Team will be determined. The young hopefuls include Jordan Burroughs, a two-time NCAA champ at Nebraska who won a world championship at 74kg in 2011. The veterans include three-time Olympian Dennis Hall, who is attempting to make another Olympic team at age 41.

Of the 18 Olympic weight classes, the United States is qualified for the London 2012 Olympic Games in 16. U.S. wrestlers will attempt to gain Olympic slots in the other two weight classes (60kg men’s freestyle, 96kg Greco-Roman) at international qualifying tournaments. The weight classes include seven in men’s freestyle and Greco-Roman, and four in women’s freestyle.

Both Saturday and Sunday, challenge rounds will be held during the day in six-hour sessions, followed by the final round each night. In the finals, the top seed will face the winner of the challenge round in a best-of-three series.

Among the returning Olympians trying to snag another spot for London is Henry Cejudo, who was the youngest wrestler in U.S. history to win gold at age 21 at the Beijing 2008 Olympic Games. “I feel good. I’m ready and I’m excited,” Cejudo said.

arrie Johnson, a two-time Olympian, and Ryan Dolan will be paddling for Olympic spots Friday at the U.S. Olympic Trials for Flatwater Sprint in Oklahoma City. If they win, they will qualify for the Games in London, pending nomination by the U.S. Olympic Committee.

“I am really excited to race for a spot on my third Olympic team,” said Johnson, who qualified the Olympic slot for the United States by winning gold at the 2011 Pan American Games. “I know that everyone has been training very hard and there is going to be some great racing.”

Johnson will compete in the women’s single kayak 500-meter race. Dolan, who qualified an Olympic slot by winning bronze at the Pan Am Games, will compete in the men’s single kayak 200-meter race. If Johnson or Dolan don’t win their competitions, the U.S. Olympic race will move on to the first World Cup event in May in Germany.

The event continues Saturday with the Senior, U-23 and Paracanoe National Team Trials on the Oklahoma River.

TABLE TENNIS

North American Olympic Trials, April 20-22, Cary, N.C.

Ariel Hsing, a 16-year-old high school student who placed second to four-time Olympian Jun Gao in the U.S. Olympic Trials for table tennis two months ago, is among eight U.S. athletes who’ll battle four Canadians for Olympic spots at the North American Olympic Trials. The event begins Friday at the Bond Park Community Center in Cary, N.C.

At stake are three men’s Olympic spots and two women’s spots, plus two team Olympic berths. Mo Zhang of Canada has already clinched one women’s spot at the London 2012 Olympic Games because she won gold at the Pan American Games.

Other U.S. women competing are Lily Zhang, Erica Wu and Judy Hugh. Gao, who would have been the top player for the United States, withdrew due to an injury. Competing on the men’s side for the United States are Michael Landers, Barney Reed Jr., Timothy Wang and Adam Hugh.

FIGURE SKATING

ISU World Team Trophy, April 19-21, Tokyo

Led by a first-place performance by Olympic silver medalists Meryl Davis and Charlie White in ice dancing, Team USA is currently in second place behind host nation Japan for second place at the ISU World Team Trophy in Tokyo. The event continues through Saturday.

Daisuke Takahashi of Japan won the men’s event, followed by two-time Canadian world champion Patrick Chan and American Olympian Jeremy Abbott dropped from third to fifth overall. Another U.S. skater, Adam Rippon, placed seventh. U.S. pairs skaters Caydee Denney, a 2010 Oympian, and her partner, John Coughlin, are in fifth place. The pairs’ free skate and women’s free skate are Saturday. U.S. national champion Ashley Wagner and 2011 U.S. junior titlist are competing in the women’s event.

Team USA was in sixth place in the team competition after the technical routine Thursday at the FINA Olympic Games Qualification Tournament in London. The free routine will be held Saturday, and the top three teams will earn berths in the London 2012 Olympic Games for their countries.

In the duet competition, Killman and Koroleva will compete Friday in the free routine. They were in seventh place after Wednesday’s duet technical competition. The second round of the duet free will be Sunday. Of the 33 duets in the competition, 19 will clinch Olympic spots for their nations. Five nations (Canada, China, Australia, Egypt and host Great Britain) have already qualified.

MODERN PENTATHLON

UIPM World Cup, April 19-22, Rostov, Russia

Mickey Kelly and Rendy Opdycke each placed seventh in their qualifying groups Thursday, and advanced to the women’s finals of the Rostov World Cup in Russia. Kelly totaled 3,968 points, finishing seventh in the combined run/shoot, 10th in fencing and 22nd in the swim. Opdycke totaled 3,888 points and had a fourth-place finish in the swim. They will compete in the women’s finals Saturday.

Dennis Bowsher, already nominated to the 2012 Games, will join 2008 Olympians Sam Sacksen and Eli Bremer, plus Will Brady in Friday’s qualification round for the men. The finals are Sunday. The Rostov World Cup is the fourth World Cup competition of the season, and counts toward qualification for the World Cup Final and potentially Olympic qualification.

EQUESTRIAN

Rolex/FEI World Cup Final, April 17-22, ’s-Hertogenbosch, Netherlands

Rich Fellers guided Flexible to a clear round in Thursday’s first round of the Rolex/FEI World Cup Final, taking first place over Switzerland’s Steve Guerdat. Flexible’s time was 60.26 seconds.

Kirsten Coe, aboard Baronez, was in eighth place. There are three more rounds to the competition.

Jan Ebeling, riding Rafalca, and Shawna Harding, aboard Come On III, will represent the United States in the Reem Acra FEI World Cup Dressage Final on Friday. Harding drew the 16th position in the order of competition and Ebeling will be the 18th and final rider, positions that pleased USEF Dressage Technical Advisor Anne Gribbons.

Also in equestrian:

National Reining Breeders Classic, April 16-22, Katy, Texas

TENNIS

USA vs. Ukraine, Fed Cup, April 21-22, Kharkiv, Ukraine

Serena Williams, a two-time Olympic gold medalist in doubles, will lead the United States into its Fed Cup group playoff match Saturday and Sunday against Ukraine. Williams has never lost a Fed Cup match, and she will play in singles this weekend.

Also playing for the United States will be Christina McHale, Sloane Stephens and Liezel Huber, the world’s top-ranked doubles player. Olympic hopeful Venus Williams will not play because she is recovering from the fatigue-causing Sjögren’s Syndrome.

DIVING

FINA Diving World Series, April 20-21, Tijuana, Mexico

Coming off a FINA Diving World Series last week in which the United States won four medals, Team USA begins competition Friday in the last leg of the World Series in Tijuana, Mexico. David Boudia won two medals last week in Moscow: bronze in the men’s 10-meter and silver in the men’s synchronized 10-meter with Nick McCrory.

Myles Porter, a gold medalist at the Parapan American Games; Katie Davis, a silver medalist at the Parapan Games; and Jordan Mounton, a bronze medalist at the 2011 IBSA World Games, will be among the athletes seeking a spot on the U.S. Paralympic Games Team (visually impaired) when they compete this weekend at the Paralympic Trials in Irving, Texas.

The event, to be held at the Irving Convention Center, also includes the USA Judo Senior National Championships for more than 320 athletes. Porter, a resident athlete at the U.S. Olympic Training Center in Colorado Springs, will compete at 100kg. The United States is qualified for the London 2012 Paralympic Games in men’s 90kg and 100kg, and women’s 57kg and 70kg-plus.

The U.S. Men’s National Under-18 Team will face Canada in the semifinals of the IIHF Men’s World Under-18 Championships on Friday. The game is a rematch of Team USA’s 5-3 win over Canada on Tuesday in its final preliminary-round game at Kajot Arena in Brno, Czech Republic.

Team USA won all four of its preliminary-round games, three of them by shutout. A win Friday would put Team USA in Sunday’s gold-medal game.

VOLLEYBALL

FIVB Swatch World Tour, Brasilia Open, April 18-21, Brazil

Matt Fuerbringer and Nick Lucena swept into the third round of the Brasilia Open after a 21-19, 21-12 victory Thursday over Steven Grotowski and John Garcia-Thompson of Great Britain, and a 23-21, 21-14 win over Germany’s Sebastian Dollinger and Stefan Windscheif. Fuerbringer and Lucena, the No. 4 seeds, are the only U.S. men’s team left in the winners’ bracket. Top-ranked Phil Dalhausser and Todd Rogers, and No. 10 Jake Gibb and Sean Rosenthal are in the consolation bracket.

The top-seeded women’s team of Misty May-Treanor and Kerri Walsh finished tied for fifth place following a loss to No. 2 Larissa Franca and Juliana Felisberta Da Silva of Brazil.

SHOOTING

ISSF World Cup, April 19-28, London

Matt Emmons, a two-time Olympic medalist, is among 14 U.S. Olympians and 32 U.S. shooters overall who will compete in the International Shooting Sports Federation (ISSF) World Cup in London. The competition, held at the Royal Artillery Barracks Range, is a test event for the London 2012 Olympic Games.

The U.S. team also includes four-time Olympian Daryl Szarenski, 2008 Olympic bronze medalist Jason Turner and three-time Olympian Jason Parker.

“For me, the London World Cup is the most important World Cup of the year, if not the quad, because I think it will build a familiarity with the range and what’s going on around you,” said 2008 Olympian Keith Sanderson.

The U.S. Women’s National Field Hockey Team will face Australia on Saturday in the second Four Nations series in New Zealand. The United States is 1-1 following a 3-0 win over India on Wednesday and a 3-2 loss to New Zealand on Thursday. In two series of games, the United States is 2-3-1.

“Scoring three goals is always good, but if there is an area of improvement we will look at, it is ruthlessness in the scoring zone,” said assistant coach Nick Conway. “We will look to improve our ability to turn our opportunities into goals.”

ARCHERY

Easton Foundations Gator Cup, April 19-21, Newberry, Fla.

The tournament is part of the qualifier series for the U.S. Archery Team. It continues through Saturday at the Easton Newberry Sports Complex, and is expected to include many of the nation‘s top archers. The tournament comes one week before the second round of the Olympic Trials for men’s and women’s recurve archers take place in Chula Vista, Calif.

A combined 11 men’s and women’s top 10 finishers from 2011 are among a field of nearly 1,300 competitors in the USA Triathlon Collegiate National Championship. Rudy Kahsar of Colorado, the 2011 men’s champion, and Erika Erickson of California, the No. 5 finisher last year in the women’s race, are among the returnees.

More than 300 gymnasts, including 22 from the United States, are competing in the Acrobatic Gymnastics World Age-Group Competition in Lake Buena Vista, Fla. The event, following up the World Acrobatic Championships earlier this week, began with podium training Thursday at the ESPN Wide World of Sports Complex.

Also in gymnastics:

NCAA Women’s Gymnastics Championships, April 20-22, Duluth, Ga.

NCAA Men’s Gymnastics Championships, April 19-21, Norman, Okla.

Story courtesy Red Line Editorial, Inc. Paul D. Bowker is a freelance contributor for teamusa.org. Material from various news services and press releases from National Governing Bodies was used to compile this report. This story was not subject to the approval of any National Governing Bodies.